1. Field of the Invention
This disclosure is directed to a method of controlling copy protection in digital video networks where it is desired to copy protect an analog or digital video output signal associated with a digital video network.
2. Background of the Invention
Various well known copy protection schemes for video signals include that disclosed in U.S. Pat. No. 4,631,603, John O. Ryan, Dec. 23, 1986 and assigned to Macrovision Corporation, incorporated by reference, directed to modifying an analog video signal to inhibit making of acceptable video recordings therefrom. This discloses adding a plurality of pulse pairs to the otherwise unused lines of a video signal vertical blanking interval, each pulse pair being a negative-going pulse followed closely by a positive-going pulse. The effect is to confuse AGC (automatic gain control circuitry) of a VCR (video cassette recorder) recording such a signal, so that the recorded signal is unviewable due to the presence of an excessively dark picture when the recorded signal is played back.
Another analog video protection scheme is disclosed in U.S. Pat. No. 4,914,694 issued Apr. 3, 1990, to Leonard, and assigned to Eidak Corp., incorporated by reference. The Eidak system (see Abstract) increases or decreases the length of each video field from the standard length, either by changing the time duration of the respective horizontal line intervals in each field while keeping a constant, standard number of lines per frame, or by changing the number of horizontal line intervals which constitute a frame while maintaining the standard duration of each line interval.
These video protection systems modify the video signal to be recorded (for instance on tape) or to be broadcast (for instance protected pay-per-view television programs) to make copying by ordinary VCRs difficult or impossible. When a video tape on which is recorded the copy protected video signal is played back for viewing using a VCR, the copy protection process is essentially transparent, i.e., it does not interfere with viewing. However, any attempt made to copy the video signal from the tape using a second VCR to record the output of the first (playback) VCR yields a picture degraded to some extent, depending on the efficacy of the particular copy protection system. These present video copy protection systems protect only analog video signals, which are the type of video signals broadcast and recorded using current consumer video technology.
Some digital and hybrid solutions to the copy protection problem were solved by U.S. Pat. No. 5,315,448, issued May 24, 1994, issued to Ryan and assigned to Macrovision Corporation, incorporated by reference. This patent is directed to copy protection for use with digital signal recording where it is desired to copy protect both an analog and digital signal associated with a digital VCR, and any signal material where the original source material is not copy protectable.
A fundamental revolution is under way that will dramatically affect the delivery of home entertainment. Consumers will soon have hundreds of viewing options from which to choose because of advances in digital compression technologies and the associated reduction in costs accompanying each advance. Because of the increased number of channels more channels will be allocated for pay-per-view (PPV). The increased number of PPV channels will mean video service providers (VSP), also known as PPV providers or system operators, can provide a greater number of movies and more start times, ultimately changing the way many consumers purchase and view movies in their homes. Already, market research experts are predicting that the pay-per-view business will rival today""s videocassette rental and sell-through business within 3-5 years.
Even with such a positive outlook for the future of PPV, the full benefits to the consumer of PPV programming may be delayed unless new digital video networks can protect PPV program copyrights. Rights owners are concerned that when digital programming is delivered to the home any digital set-top box will be able to produce a commercial quality video when recorded by a consumer VCR.
In this new world of direct-to-home video programming, video service providers will be called upon to protect PPV programming against unauthorized copying. They will be obligated to develop and manage the headend (cable) or uplink (satellite) systems which monitor, control, track, and report the application of copy protection on each pay-per-view video program. To this end, the present invention provides copy protection management framework which meets these needs while complementing the more technically detailed copy protection management strategy for video service providers. This framework serves to integrate all components of copy protection delivery in a digital network, and is designed to fit the diverse needs of DBS, Telco, and Cable operators while meeting the requirements of rights owners for a robust and secure environment in which to deliver copy protected PPV programming.
The value of PPV copy protection is maximized when the appropriate control and tracking systems are in place at the video service provider""s control and billing centers. These control and tracking systems are best specified during the design phase of the digital signal material delivery system. At a minimum, the following system components are required:
Copy protection-capable set-top boxes
Capability to deliver programmable copy protection configuration
Capability to deliver real time on/off/mode command
Transaction/billing reporting systems/programs
A control and tracking system in accordance with the invention, for providing copy protection for a typical digital delivery system can be best understood through a short case study which begins when a consumer, that is a subscriber, receives a new set-top box. Each set-top box includes a copy protection capable digital-to-analog encoder chip. When the set-top box is initially powered on, the encoder chip is remotely programmed via a video service provider with the desired copy protection configuration. Thus the video service provider""s system management software (SMS), also termed hereinafter as system control software (SCS), has the ability to store and track the designated configuration. The configuration information applies to all copy protected programming and is updated only when a video service provider is informed of a change in the process or when a set-top box is initialized.
The copy protection status or option of each program is contained in the video service provider""s system control software database. There are several potential copy protection status options. For example, a first option is for copy protection which allows for viewing only at a PPV transaction fee. A second option is for copy protection which allows for taping at a higher transaction fee. A third option is for non-protected program material for which no copy protection is required (for example, broadcast television).
When the consumer selects a viewing choice via an electronic program guide, a correct menu of options is displayed. Once a PPV program is selected by the consumer, the correct copy protection status is applied as determined by the consumer""s chosen option and scheduling software of the system control software database. Either the headend/uplink facility""s control software or software at the set-top box can determine and send the appropriate on/off/mode command to the copy protection capable digital-to-analog chip of previous mention.
The headend/uplink software communicates the on/off/mode command to the set-top box to correctly set the copy protection for a particular program. The system scheduling software has the capability to prevent copy protection from being applied to any type of program other than PPV programming since copy protection is licensed only for use on PPV programming. After a PPV program is viewed by a consumer, the set-top box is able to communicate to a billing subsystem of the system control software all relevant transaction data. From this data the billing subsystem is able to add this information to copy protection activity reports. These reports contain information such as the number of purchases, retail price, and copy protection usage fees owed to a licensor.
The copy protection process is applied to the analog video signal just prior to its exiting the consumer""s set-top box. The application of the copy protection process is controlled and managed by system control/access software of the system control software that resides in the video service provider""s operations control and billing center.
All set-top boxes in the network need to contain copy protection circuitry. If a set-top box does not have copy protection capability then the video service provider is able to identify those set-top boxes and deny them copy protected PPV programming.